The proposed law that would require doctors to notify parents of minors seeking abortions was defeated, according to results released this morning.

Proposition 4, a ballot initiative supported by anti-abortion advocates and opposed by Planned Parenthood and other abortion rights organizations, was one of the tightest races among the statewide propositions.

Early returns showed the race seesawing, but with 96.4 percent of the precincts reporting as of 10:30 a.m., the No on 4 campaign has received 52.4 percent of the votes.

“We think we’ve probably crossed over where the numbers aren’t going to switch,” No on 4 spokeswoman Kathy Kneer said late Tuesday night.

Late Tuesday, Yes on 4 campaign strategist Charles Gallagher had hoped for a favorable turnout from Latinos in Los Angeles and the Central Valley.

A defeat would make it the third such proposition in three years to fail at the ballot box.

Voters rejected parental notification measures in 2005 and 2006, but this year, recent polling showed more support than opposition.

The initiative would have required a doctor to notify the parents or legal guardian of an unemancipated minor at least 48 hours before performing an abortion requested by the teenager. Although a parent may object, the girl still would have the right to an abortion.

There were a few exceptions: If the girl lives with an abusive family, for example, the notification can be made to an adult relative. Parental notification also may be waived if the girl is undergoing a medical emergency, or if she succeeds in persuading a juvenile court to forgo the notification.

A University of California-Davis professor placed Proposition 4 on the ballot. The proposition applied to girls who are younger than 18, not married and not active in the military.

The proponents pitched it as a measure to protect teenage girls from adult predators. Yes on 4 ads told of men who sexually exploited teens and made them get abortions at clinics where the workers didn’t call authorities to report child abuse.

“We need to protect young girls from the dangers of secret abortions, not just the physical dangers but the emotional dangers,” said Katie Short, an attorney with Life Legal Defense and co-author of the initiative.

The opposition, led by Planned Parenthood Affiliates of California, counters that the proposal threatened the health and safety of girls whose parents may react violently when notified that their daughter is pregnant. The No on 4 campaign said that the measure might mean that pregnant girls “may take matters into their own hands” through illegal and self-induced abortions.

“This is the third attempt by anti-choice extremists to put the health of teens at risk in California to serve their political agenda,” said Kneer, president of Planned Parenthood Affiliates. “The worst-case scenario,” Kneer said, “is this law would be implemented Feb. 6 and completely turn the courts upside down as they try to grapple with how to implement this law.”